| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Yijun Lin |
| Physics operator(s): | Ron Parker,Steve Wolfe,Ron Parker |
| Engineering operator(s): | Bill Cochran,Bill Byford,Bill Cochran,Bill Byford |
| Engineering Operator Run Comment |
| MP#417 Post-boronization evaluation |
| Session Leader Plans |
| Entered: May 3 2005 08:19:52:637AM |
| Author: Yijun Lin |
| SL_PLAN: 1050503
MP 417. Post-boronization evaluation Setup: Li pellet and boron injectors may be needed. Run load shot 1050426022 (possibly at a slightly different density) Background: Boronization done only to the outer limiter and antennas. ECDC in D2 prior to the first plasma. We need to evaluate whether such boronization is effective, and whether it is as effective as the previous two boronizations, 1050419 (outer divertor only) and 1050425 (outer divertor together with outer limiter and antennas) Goal 1. Evaluate boronization by running constant discharges. 2. Evaluate the trend of impurities levels in the plasma Plan: 1. Load shot 1050426022 (including D2 puff in H-mode). Slightly modified RF waveform. 3 MW from 0.7 to 0.95 sec, 4 MW from 0.95 sec to 1.15 sec, and 5 MW from 1.15 to 1.5 sec. Do a density scan in the first 3 shots, target density at nl = 1.1, 0.9, 1.3e20 m^-2. For the subsequent shots, choose the density that give the best long EDA H-mode Assess the boronization effectiveness using the first 15 plasmas. 2. Decision point. A. If the performance is excellent (Wtot >= 170 kJ at 3 MW RF), we will continue running the same 1 MA plasmas until we see definite degradation of performance. (criterion: Wtot <~ 150 kJ at 1 MA and 3 MW Prf.) the run will stop as soon as there are three consecutive plasmas meeting the degradated performance criterion. In this case, we possibly run until 9 pm. No boronization will be followed. B. If the boronization has worn out substantially after 15 plasmas (150 kJ < Wtot < 165 kJ at 3 MW, 1 MA), we will continue 1 MA shot until we see three plasmas with Wtot <~ 150 kJ at 3 MW and 1 MA. If time allows (earlier than 5 pm), we will try boron shaker to inject boron to the outer limiter. We will also try Li-pellet injection. And see whether there is an improvement on the performance. In this case, the run will probably stop at 5 pm. No boronization will be followed. C. If the boronization is shown to be a "bust" (3 consecutive plasmas at Wtot < 150 kJ at 1 MA, 3 MW Prf), we will try the boron shaker and Li-pellet injections. We may also do N2 puff into RF heated L-mode and identify the dominant Mo sources. In this case, the run will definitely stop at 5 pm. Following this run, we will boronize the machine in a "normal" (to be defined) way. |
| Physics Operators Plans |
| Entered: May 2 2005 06:53:18:200PM |
| Author: Ron Parker |
Engineering setup for Tuesday, 3 May 2005 MP 417: Post-boronization evaluation Session leader: Y. Lin Physics operator: R. Parker Boronize overnight, followed by 2+ hours of ECDC in D2; bake at 60 C. Run begins at 09:00 and possibly ends at 21:00. Power systems as on 1050429001 (Fidicial plasma) A-coil configuration: normal [+Dtop -Dbot -Jtop +Jbot] and enabled. Gas Setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 2 psi Ar Hybrid enabled (PG1) leave B-side upper with whatever Hybrid disabled fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3) fill NINJA with 8 psi N2 Leave disabled to begin with Torvac setup: Gate Valves closed on first shot, open thereafter. Enable the following gate valves, assuming no vacuum problems: ECE, VUV, Z-bolo shutters Necessary diagnostics: Core/confinement incl. bolometry, pedestal profiles, H/D, boron and molybdenum monitoring ------------------------------------------------------------------------------- ICRF Setup: All transmitters in run on at 8:30 ------------------------------------------------------------------------------- Run plan: Start with shot 1050429001 (Fiducial plasma) After Boronization Recovery: Session Leader Plan: 1. Load shot 1050426022 (including D2 puff in H-mode). Slightly modified RF waveform. 3 MW from 0.7 to 0.95 sec, 4 MW from 0.95 sec to 1.15 sec, and 5 MW from 1.15 to 1.5 sec. Do a density scan in the first 3 shots, target density at nl = 1.1, 0.9, 1.3e20 m^-2. For the subsequent shots, choose the density that give the best long EDA H-mode Assess the boronization effectiveness using the first 15 plasmas. 2. Decision point. A. If the performance is excellent (Wtot >= 170 kJ at 3 MW RF), we will continue running the same 1 MA plasmas until we see definite degradation of performance. (criterion: Wtot <~ 150 kJ at 1 MA and 3 MW Prf.) the run will stop as soon as there are three consecutive plasmas meeting the degradated performance criterion. In this case, we possibly run until 9 pm. No boronization will be followed. B. If the boronization has worn out substantially after 15 plasmas (150 kJ < Wtot < 165 kJ at 3 MW, 1 MA), we will continue 1 MA shot until we see three plasmas with Wtot <~ 150 kJ at 3 MW and 1 MA. If time allows (earlier than 5 pm), we will try boron shaker to inject boron to the outer limiter. We will also try Li-pellet injection. And see whether there is an improvement on the performance. In this case, the run will probably stop at 5 pm. No boronization will be followed. C. If the boronization is shown to be a "bust" (3 consecutive plasmas at Wtot < 150 kJ at 1 MA, 3 MW Prf), we will try the boron shaker and Li-pellet injections. We may also do N2 puff into RF heated L-mode and identify the dominant Mo sources. In this case, the run will definitely stop at 5 pm. Following this run, we will boronize the machine in a "normal" (to be defined) way. |
| Session Leader Summaries |
| Entered: May 3 2005 05:17:47:713PM |
| Author: Yijun Lin |
| SL summary: post-boronization recovery
Total 29 shots. 26 fizzles/earlier disruptions (shorter than 130 ms) 1 dud 2 no power shots |
| Physics Operator Summaries |
| Entered: May 3 2005 05:26:05:213PM |
| Author: Ron Parker |
| The run was very disappointing in that at best only extended (100 ms)
fizzles could be produced. The run followed Boronization during the prior evening, and before that, over the weekend, there was a backfill of the machine for Thomson calibration. During the calibration substantial amounts of dust were observed in the machine, and the dust also could be seen in the plasma light for the longer shots. Although the run had been scheduled to last until 9:00 it was terminated at 5:15 since progress in producing good plasma shots was very slow. At this point, the root cause of the fizzles is unknown -- Boronization ? -- Dust? -- Other? The plan is to consider overnight discharge clean in He and hope for better plasmas tomorrow. |
| Session Leader Comments | |||
| May 3 2005 08:58:53:717AM | 1050503001 | Yijun Lin | fiducial shot attempt. fizzle |
| May 3 2005 10:09:00:840AM | 1050503002 | Yijun Lin | fizzle |
| May 3 2005 10:09:05:997AM | 1050503003 | Yijun Lin | fizzle |
| May 3 2005 10:20:09:013AM | 1050503004 | Yijun Lin | fizzle |
| May 3 2005 10:33:55:107AM | 1050503005 | Yijun Lin | fizzle/early disruption.
|
| May 3 2005 10:45:10:497AM | 1050503006 | Yijun Lin | fizzle |
| May 3 2005 10:59:55:887AM | 1050503007 | Yijun Lin | fizzle/early disruption |
| May 3 2005 11:16:16:113AM | 1050503008 | Yijun Lin | fizzle |
| May 3 2005 11:24:48:783AM | 1050503009 | Yijun Lin | fizzle/early disruption (to 75 ms). |
| May 3 2005 11:42:54:133AM | 1050503010 | Yijun Lin | fizzle |
| May 3 2005 11:55:46:620AM | 1050503011 | Yijun Lin | early disruption (to 110 ms) |
| May 3 2005 12:08:11:963PM | 1050503012 | Yijun Lin | early disruption (to 90 ms) |
| May 3 2005 12:30:41:840PM | 1050503013 | Yijun Lin | up to 75 ms |
| May 3 2005 12:36:20:743PM | 1050503014 | Yijun Lin | to 120 ms |
| May 3 2005 01:14:05:650PM | 1050503015 | Yijun Lin | to 120 ms |
| May 3 2005 01:14:37:260PM | 1050503016 | Yijun Lin | to 80 ms |
| May 3 2005 01:14:54:633PM | 1050503017 | Yijun Lin | to 100 ms |
| May 3 2005 01:27:26:307PM | 1050503018 | Yijun Lin | dud. No gas |
| May 3 2005 01:39:36:887PM | 1050503019 | Yijun Lin | 120 ms. 340 kA. |
| May 3 2005 01:56:17:837PM | 1050503020 | Yijun Lin | similar to shot 19. |
| May 3 2005 02:12:13:417PM | 1050503021 | Yijun Lin | fizzle |
| May 3 2005 02:19:47:667PM | 1050503022 | Yijun Lin | fizzle |
| May 3 2005 02:32:08:010PM | 1050503023 | Yijun Lin | fizzle |
| May 3 2005 02:51:00:650PM | 1050503024 | Yijun Lin | fizzle
ECDC in He for 1 hour. |
| May 3 2005 04:20:18:853PM | 1050503025 | Yijun Lin | no power shot |
| May 3 2005 04:32:48:853PM | 1050503026 | Yijun Lin | no power shot
|
| May 3 2005 04:49:10:603PM | 1050503027 | Yijun Lin | fizzle
|
| May 3 2005 05:06:48:510PM | 1050503028 | Yijun Lin | to 400 kA, 130 ms. better. Record amount of gas coming off the
wall afte the disruption (Blip). |
| May 3 2005 05:14:22:650PM | 1050503029 | Yijun Lin | fizzle |
| Physics Operator Comments | |||
| May 3 2005 08:51:09:810AM | 1050503001 | Ron Parker | The first shot will be the fidicial shot 1050429001 |
| May 3 2005 09:06:48:747AM | 1050503001 | Ron Parker | First shot was a fizzle, H-alpha shows breakdown at 6+ ms.
Bz is negative, -2 mT at 5 ms exactly as in shot 1050429001. We'll repeat this shot with no changes -- if fizzle, we'll increase Bz. |
| May 3 2005 09:17:18:763AM | 1050503001 | Ron Parker | Delay due to data system hangup -- PC DAC 1 (Fast MHD) |
| May 3 2005 09:31:09:527AM | 1050503002 | Ron Parker | Shot 2 also fizzled. Compared to shot 1 on the 29th, the gas is
significantly higher, ~ .05 mTorr compared with .03 mTorr. So we'll take 3 ms off the prefill for next shot. |
| May 3 2005 10:03:29:950AM | 1050503002 | Ron Parker | Another delay due to data system hangup. Also several cell entries.
Some data from shot will be lost. Ready to go at 10:05. |
| May 3 2005 10:13:41:183AM | 1050503003 | Ron Parker | Shot 3 fizzled again, albeit it lasted somewhat longer.
For the next shot we've increased Bz by ~ 1 mT (15 A on EF4) and also further reduced the fill pressure by 2 ms. |
| May 3 2005 10:26:21:653AM | 1050503004 | Ron Parker | Another fizzle, still sluggish burnout. Try again with 2 ms less gas. |
| May 3 2005 10:42:33:060AM | 1050503005 | Ron Parker | Making a little progress, but shot disrupted early due to slow current rise.
We'll continue lowering fill pressure, 2 ms more down to 9 ms. Also, Voltage on PG3 reduced to 70 volts then 100. |
| May 3 2005 10:48:36:433AM | 1050503006 | Ron Parker | Still problems. Very poor current rise.
Since we are having gate valve problems, we will henceforth open gate valves. |
| May 3 2005 11:02:29:763AM | 1050503007 | Steve Wolfe | Shot#7: Wolfe taking over as physop from Parker.
No PCS changes, but stop closing the gate valve in pulse. Another fizzle/shorty; gets to 75msec. base pressure was 3.2e-6 before the shot. Pressure started below 20uTorr, but is still rising. Still getting injections or hitting something after 45msec. Next shot: pg3 in seg1 down to 50V |
| May 3 2005 11:13:19:707AM | 1050503008 | Steve Wolfe | Shot#8: Pg3 in seg1 down to 50V, leave pg4 at 9msec. Turn off bside lower. Shouldn't have been on. Also, after this shot, have them pump it down to 1psi Argon Fizzle. Never made it to the 20msec point, so change in pg3 was irelevant. next shot: raise pg4 by 2msec, take another 5A off ef4 |
| May 3 2005 11:27:50:357AM | 1050503009 | Steve Wolfe | Shot#9: raise pg4 by 2msec to 11ms, take another 5A off ef4 to 1345 Another shorty, about 75msec, almost lost it at 20msec. big lump on the z-meter signal after 10msec. pressure rise is slower, still gets to 50uTorr at 40msec, from 20 at t=0 next shot: raise pg4 to 13msec |
| May 3 2005 11:45:28:947AM | 1050503010 | Steve Wolfe | Shot#10: raise pg4 by 2msec to 13ms, fizzle. Huge lump on zmeter at 10msec, big jump on halpha at 20msec, and then it's all over. next shot: raise Br by .3mT |
| May 3 2005 11:59:12:980AM | 1050503011 | Steve Wolfe | Shot#11: raise Br0 by .3mT to -.0002T base pressure in check is 2.6e-6 That one got to 110msec, Still getting a big burst on the zmeter, and a hesitation in the current rise between 15 and 20ms. Current is <300kA at 0.1sec next shot: reduce pg3 in seg1 |
| May 3 2005 12:11:09:400PM | 1050503012 | Steve Wolfe | Shot#12: reduce pg3 in seg1 to 20V. Under 100msec, only 200kA No lump on the z-meter. still hesitates early. Apparent injection at 56msec, ugly after that. Next shot: Jim is having the Boron Injector gate valve closed. No PCS changes |
| May 3 2005 12:25:05:917PM | 1050503013 | Steve Wolfe | Shot#13: Jim is having the Boron Injector gate valve closed, because he thinks there is a leak in it. No PCS changes Shorter, around 75msec, still and injection (or marfe?) at 60msec, and the early zmeter lump is back. next shot: raise pg4 by 2msec |
| May 3 2005 12:37:03:493PM | 1050503014 | Steve Wolfe | Shot#14: raise pg4 by 2msec to 15msec 125msec, 300kA, still has injections, still has lump on zmeter, but smaller. next shot: turn off pg3 puff in seg1, another 10A off ef4 |
| May 3 2005 12:49:09:400PM | 1050503015 | Steve Wolfe | Shot#15: turn off pg3 puff in seg1, another 10A off ef4 to -1335A Another shorty, 128ms but only 240kA. Parker taking over again. |
| May 3 2005 12:54:33:197PM | 1050503015 | Ron Parker | Shot was similar to previous shot, lasting about 120 ms.
Significant dust appearing on LH camera view of grill. Current is resistive during current rise, reaching only half of nominal value before disruption. |
| May 3 2005 01:12:12:120PM | 1050503016 | Ron Parker | Shot 16 was again short, ending at about 80 ms.
Anyone for discharge cleaning? |
| May 3 2005 01:22:20:307PM | 1050503017 | Ron Parker | Shot 17 was the best so far, the current reached nearly 300 kA and seemed
slightly less resistive. |
| May 3 2005 01:28:23:527PM | 1050503018 | Ron Parker | Shot 18 was a dud, due to a failure of prefill valve to open.
Try again. |
| May 3 2005 01:44:05:540PM | 1050503019 | Ron Parker | Still getting a bit less resisitive.
Steve suggests lower the demand for current at 100 ms to correspond to the current that we actually achieve (300 kA). done for next next shot. |
| May 3 2005 02:03:33:040PM | 1050503020 | Ron Parker | For the next shot, we've reinstalled pg 3 @ ~ 60 volts for 100 ms. |
| May 3 2005 02:11:36:087PM | 1050503021 | Ron Parker | This shot was a short fizzle. The fill pressure has come down to .022 mT at breakdown. Add 2 ms to prefill -- 15 ms to 17 ms |
| May 3 2005 02:25:59:073PM | 1050503022 | Ron Parker | Shot 22 was another short fizzle. Ian suggests to change Rcur Offset, which we've
done for next shot, from 2500 to 2000. We've also added two more ms of pulse gas prefill. |
| May 3 2005 02:38:23:633PM | 1050503023 | Ron Parker | Still fizzling early.
Changing BR offset seemed to help a tad, so we'll go further in this direction, to 1500. Also, changed BR offset to -.0005 |
| May 3 2005 02:48:29:230PM | 1050503024 | Ron Parker | More fizzling.
There will be a break in the "action" while we discharge clean in He for 1 hour. |
| May 3 2005 04:37:03:680PM | 1050503025 | Ron Parker | Shot 25 was a no power shot. Try Again.
Between shot 24 and 25 we had ~ 1 hour of ECDC in Helium. Shot 25 was programmed to be the same as shot 24. |
| May 3 2005 04:41:14:527PM | 1050503026 | Ron Parker | Shot 26 was a no power shot. Continue to be plagued by
data system hangups. |
| May 3 2005 04:51:56:900PM | 1050503027 | Ron Parker | Shot 26 was a marginally better fizzle than shot 24, which was the last shot
before discharge cleaning. Next: Load shot 1050426001. |
| May 3 2005 05:09:17:370PM | 1050503028 | Ron Parker | Shot 28 was the best of the day, reaching 400 kA and lasting ~ 130 ms.
Try one more time: bette: continue; worse: end run. |
| May 3 2005 05:16:04:853PM | 1050503029 | Ron Parker | Shot 29 fizzled. This ends the run. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:57:04:670AM | Plasma | Ok | |
| 2 | 09:24:14:683AM | Plasma | Ok | |
| 3 | 10:05:34:090AM | Plasma | Ok | |
| 4 | 10:18:12:607AM | Plasma | Ok | |
| 5 | 10:30:48:387AM | Plasma | Ok | |
| 6 | 10:43:26:247AM | Plasma | Ok | |
| 7 | 10:56:12:310AM | Plasma | Ok | |
| 8 | 11:09:06:357AM | Plasma | Ok | |
| 9 | 11:22:09:740AM | Plasma | Ok | |
| 10 | 11:41:01:777AM | Plasma | Ok | |
| 11 | 11:53:25:730AM | Plasma | Ok | |
| 12 | 12:05:58:230PM | Plasma | Ok | |
| 13 | 12:21:20:527PM | Plasma | Ok | |
| 14 | 12:33:52:540PM | Plasma | Ok | |
| 15 | 12:46:30:853PM | Plasma | Ok | |
| 16 | 12:59:11:430PM | Plasma | Ok | |
| 17 | 01:11:47:760PM | Plasma | Ok | |
| 18 | 01:24:26:057PM | Plasma | Ok | |
| 19 | 01:37:05:353PM | Plasma | Ok | |
| 20 | 01:49:51:837PM | Plasma | Ok | |
| 21 | 02:03:41:230PM | Plasma | Ok | |
| 22 | 02:17:30:180PM | Plasma | Ok | |
| 23 | 02:30:03:120PM | Plasma | Ok | |
| 24 | 02:42:36:057PM | Plasma | Ok | |
| 25 | 04:09:46:260PM | Plasma | Bad | Ack Failure at Pulse |
| 26 | 04:26:03:417PM | Plasma | Bad | Actmon Failure |
| 27 | 04:46:52:807PM | Plasma | Ok | |
| 28 | 04:59:33:853PM | Plasma | Ok | |
| 29 | 05:12:00:103PM | Plasma | Ok | |